2001 Buick Century shift solenoid

p07nnn codes are tranny
23 year old car, and old cars had few trannycodes
the service manual covers this, best is to get it and read it first.
so $20 is too much to pay to read it?
I WILL NOT POST 40 PAGES OF PCM SCHEMATICS HERE. EVER.
https://eautorepair.net/Marketing/Default.asp

TDC TRANSMISSION RELAY SENDS POWER TO TCM SOLENOIDS
LIKE THIS.

P0753 Trans 3-4 Shift Sol/Trans Relay Circs

THE SERVICE MANUAL SHOWS HOW IT WORKS
Symptom:
P-0753 TRANS 3-4 SHIFT SOLENOID/TRANS RELAY CIRCUITS
When Monitored and Set Condition: (OBD2 RULES)
P-0753 TRANS 3-4 SHIFT SOLENOID/TRANS RELAY CIRCUITS
When Monitored: Continuously with the key on.
Set Condition: This code is set if the voltage detected on the 3-4 Shift Solenoid Control
Circuit at the PCM is different than the expected voltage.
POSSIBLE CAUSES
FUSED B(+) FEED TO THE TRANS CONTROL RELAY OPEN
TRANSMISSION CONTROL RELAY DEFECTIVE " TDC
3-4 SOLENOID WIRING HARNESS INTERMITTENT DEF
3-4 SOLENOID WIRING HARNESS OBSERVABLY DEF
SHIFT SOLENOID CONTROL CIRCUIT OPEN
SHIFT SOLENOID CONTROL CIRCUIT SHORT TO GROUND
SOLENOID AND HARNESS DEF (SOLENOID CONNECTOR)
SOLENOID AND HARNESS DEF (SOLENOID CONTROL CKT)
TRANSMISSION RELAY OUTPUT CIRCUIT OPEN
TRANSMISSION RELAY OUTPUT CIRCUIT SHORTED TO GND
PCM DEF (3-4 SOLENOID/TRANSMISSION)
PCM DEF (TRANS 3-4 SOL/TRANS RLY CKT)
PCM DEF (3-4 SOLENOID CONTROL CIRCUIT)
PCM DEF (SOLENOID HARNESS AND PACK)
358
TRANSMISSION

SCHEMO BINGO.

Do you know why it's stuck in park ? Do the brake lights work ?
Automatic Transmission Shift Lock Control Description and Operation (Floor Shift)
The automatic transmission shift lock control system is a safety device that prevents an inadvertent shift out of PARK when the engine is running. The driver must press the brake pedal before moving the shift lever out of the PARK position. The system consists of the following components:
• The automatic transmission shift lock solenoid (serviced as the automatic transmission shift lock actuator), as well as the body control module (BCM) and the engine control module (ECM)/powertrain control module (PCM). The shift lock solenoid is located within the floor shift control assembly with vehicles equipped with floor shift.
• The BCM controls the voltage supply circuit of the shift lock control solenoid. The following conditions must be before the BCM will supply voltage to the shift lock control solenoid.
The BCM controls the voltage to the shift lock control solenoid through the shift lock control solenoid controlled voltage circuit. The following conditions must be met before the BCM will supply voltage to the shift lock solenoid:
• The ignition is in the ON position.
• The ECM/PCM sends an input via GMLAN serial data to the BCM indicating the transmission is in the PARK position.
• The BCM determines the brake pedal is applied according the brake pedal position.
Since the shift lock control solenoid is permanently grounded, the BCM supplies voltage to the automatic transmission shift lock control solenoid, mechanically unlocking the shift lever allowing the driver to move the shift lever out of the PARK position as the solenoid energizes. When the brake pedal is not applied, the BCM turns the control voltage output of the shift lock control solenoid OFF, de-energizing the shift lock control solenoid. The de-energized solenoid mechanically locks the shift lever in the PARK position.
During remote start operation, the BCM will de-energize the shift lock control circuit, locking the shift lever in the PARK position.
Do you know what DTC'S are ?
DTC B2705 Gearshift Unlock Circuit !
The body control module (BCM) controls the shift lock solenoid by providing battery voltage to the shift lock control solenoid. The BCM utilizes a smart driver to control the voltage supplied to the shift lock solenoid. The smart driver monitors the voltage and current flow of the control circuit.

Transmission Control Lever Malfunction (Floor Shift)
Circuit/System Verification
Ignition ON, while pressing the brake pedal, observe the scan tool Brake Applied Output Signal parameter. The reading should be ON with the brake pedal pressed.
? If not the specified value, refer to Stop Lamps Malfunction .
Press the brake pedal, the vehicle operator should be able to move the shifter lever out of the park position.
With the vehicle moving over 5 km/h (3 mph), the vehicle operator should not be able to move the shift lever into the reverse position.

Define won't crank ? I'am assuming the key will turn to the start position ! When doing so does the starter spin the engine or not ? Trying to define your problem of won't crank . If when you turn the key to start position an the starter spins the engine over but doesn't start an run , this is a cranks no start condition . If nothing happens when you turn the key to start , this is a no crank no start condition . Your vehicle has a safety system , shift interlock , won't let it shift out of park if the brake pedal isn't pressed . Won't let the key turn off either . Electronics involved , locking solenoid's etc.... Floor or column shift ?
The automatic transmission shift lock control system is a safety device that prevents an inadvertent shift out of PARK when the engine is running. The driver must press the brake pedal before moving the shift lever out of the PARK position. The system consists of the following components:
• The automatic transmission shift lock solenoid (serviced as the automatic transmission shift lock actuator), as well as the body control module (BCM) and the engine control module (ECM)/powertrain control module (PCM). The shift lock solenoid is located within the floor shift control assembly with vehicles equipped with floor shift.
• The BCM controls the voltage supply circuit of the shift lock control solenoid. The following conditions must be before the BCM will supply voltage to the shift lock control solenoid.
The BCM controls the voltage to the shift lock control solenoid through the shift lock control solenoid controlled voltage circuit. The following conditions must be met before the BCM will supply voltage to the shift lock solenoid:
• The ignition is in the ON position.
• The ECM/PCM sends an input via GMLAN serial data to the BCM indicating the transmission is in the PARK position.
• The BCM determines the brake pedal is applied according the brake pedal position.
Since the shift lock control solenoid is permanently grounded, the BCM supplies voltage to the automatic transmission shift lock control solenoid, mechanically unlocking the shift lever allowing the driver to move the shift lever out of the PARK position as the solenoid energizes. When the brake pedal is not applied, the BCM turns the control voltage output of the shift lock control solenoid OFF, de-energizing the shift lock control solenoid. The de-energized solenoid mechanically locks the shift lever in the PARK position.
During remote start operation, the BCM will de-energize the shift lock control circuit, locking the shift lever in the PARK position.

Plus the reverse lock out !
The reverse lockout system is a safety feature which prevents an inadvertent shift into reverse at speeds above 5 km/h (3 mph). The system consists of the following components:
• The engine control module (ECM)/powertrain control module (PCM)
• The reverse lockout solenoid
With the ignition ON, battery voltage is supplied directly to reverse lockout solenoid. At forward speeds above 5 km/h (3 mph), the ECM/PCM commands the reverse lockout solenoid ON by grounding the control circuit of the solenoid. This energizes the solenoid and mechanically prevents the shift lever from being moved into the REVERSE position. At forward speeds below 5 km/h (3 mph), the ECM/PCM commands the reverse lockout solenoid OFF, de-energizing the solenoid, which allows the shift lever to move into the REVERSE position.

Power Mode Master
This vehicles BCM functions as the power mode master (PMM). The ignition switch is a low current switch with multiple discrete ignition switch signals to the PMM for determination the power mode that will be sent over the serial data circuits to the other modules that need this information, and so the PMM will activate relays and other direct outputs of the PMM as needed. Refer to Power Mode Description and Operation for a complete description of power mode functions.
You have no clue of the electronics in your vehicle , your best bet have it towed to the Buick dealer .

Problem with shift interlock system .
Automatic Transmission Shift Lock Control Description and Operation
The automatic transmission shift lock control system is a safety device that prevents an inadvertent shift out of PARK when the engine is running. The driver must press the brake pedal before moving the shift lever out of the PARK position. The system consists of the following components:
?€¢
The automatic transmission shift lock control solenoid

?€¢
The body control module (BCM)

?€¢
The powertrain control module (PCM)

With the ignition in the ON position, battery positive voltage is supplied to the automatic transmission shift lock control solenoid. The automatic transmission shift lock control solenoid receives a ground from the BCM. When the automatic transmission shift lock control solenoid is energized, the shift lever mechanically locked in the PARK position. When the driver presses the brake pedal the PCM sends a class 2 serial data message to the BCM. The BCM turns OFF the ground control circuit and this de-energizes the automatic transmission shift lock control solenoid. When the automatic transmission shift lock control solenoid is de-energized, the shift lever may be moved out of the PARK position. The BCM determines transaxle shift lever position through a class 2 serial data message from the PCM. The PCM receives inputs from the park/neutral position switch and determines shift lever position. When the BCM receives this information and determines that the shift lever is out of the PARK position, the automatic transmission shift lock control solenoid ground is opened.

1

Did you perform the A Diagnostic System Check - Automatic Transmission Shift Lock Control?
Go to Step 2
Go to Diagnostic System Check - Automatic Transmission Shift Lock Control

2

1. Turn ON the ignition, with the engine OFF.
2. Press and hold the brake pedal.
3. Attempt to move the shift lever out of the PARK position.

Does the shift lever move out of the PARK position?
YES - Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems
NO - Go to Step 3

3

1. Turn OFF the ignition.
2. Disconnect the automatic transmission shift lock control solenoid.
3. Turn ON the ignition, with the engine OFF.
4. Attempt to move the shift lever out of the PARK position.

Does the shift lever move out of the PARK position?
YES - Go to Step 4
NO - Go to Step 5

4

Test the A/T shift lock control circuit for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
YES - Go to Step 9
NO - Go to Step 6

5

Inspect for poor connections at the harness connector of the automatic transmission shift lock control solenoid. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 9
Go to Step 7

6

Inspect for poor connections at the harness connector of the body control module (BCM). Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 9
Go to Step 8

7

Replace the automatic transmission shift lock control solenoid. Refer to Transmission Control Replacement in Automatic Transaxle-4T40-E/4T45-E.
Did you complete the replacement?
Go to Step 9
--

8

Replace the body control module (BCM). Refer to Body Control Module Replacement in Body Control System.
Did you complete the replacement?
Go to Step 9
--

9

Operate the system in order to verify the repair.
Did you find and correct the condition?
System OK
Go to Step 2

P0700 is a informative transmission code, about some problem there; the P0733 and P0734 is the specific problem there.
I would first try changing the fluid and filter. Although the fluid may look like it is brand new, with 100K on the fluid, I can assure you that even if those miles were all highway at steady speed and no load that the fluid has deteriorated and no longer lubricating the internal parts properly and that there is some debris in the ******.If codes return and shifting problems are still present, there is definite internal failure, possibly the pump or in the clutches.
DTC P0733The powertrain control module (PCM) uses the crankshaft position (CKP) sensor, input speed sensor (ISS) and output speed sensor (OSS) to determine engine speed, input shaft speed and output shaft speed. These sensor readings are used to determine the current gear ratio and RPM slip across the torque converter. The PCM uses this information from the sensors to determine if the commanded gear matches the actual gear. During normal driving conditions, the PCM will adapt main line pressure via the pressure control (PC) solenoid to prevent slipping and harsh shifts. Shift solenoid 3 is used to apply or release third gear clutch. The PCM controls 3rd gear by controlling the ground for shift solenoid 3. The PCM will turn the solenoid OFF, open the driver circuit, when 3rd gear is commanded On to apply 3rd clutch. Shift solenoid 3 is supplied ignition voltage from the fuel pump relay whenever the PCM commands the fuel pump relay ON. DTC P0733 sets when 3rd clutch still slips after the PCM has commanded high main line pressure.DTC Parameters
DTC P0733 will set if the PCM detects an incorrect actual 3rd gear ratio when 3rd gear is commanded On when:- The condition exists for longer than 3 seconds (2001)*- The condition exists for longer than 3 seconds, 1 minute is allowed to elapse, then condition exists again for longer than 3 seconds (2000)- The high main line pressure has been commanded- The transaxle is in a forward gear- The input speed is greater than 224 RPM- The vehicle speed is greater than 5 km/h (3 mph)- The speed noise parameter = NO- The steady state ratio fail counter equals 255 for an in-gear failure, or the shift fail counter is greater than 100 on a downshift or upshift to 3rd gear (128=0 or normal operation)DTC P0733 diagnostic runs continuously once the above conditions have been met.
DTC P0733 is a type A DTC for 2000, type B for 2001.**Applicable to vehicles built after June 2000.
Diagnostic AidsImportant: If DTCs P0745, P0746, P0756, P0758, P0761, P0763, P0766, P0768 or P0789 is set, diagnose that DTC first. A diagnosed PC solenoid, shift solenoid 2, 3 or 4 low/high circuit fault DTC may have caused DTC P0733 to set.Important: If a shift solenoid performance DTC P0783, 4th gear stuck ON, is set, diagnose that DTC first. A 4th gear stuck ON may cause no 3rd gear, no 2nd gear, or TCC stuck Off.
Refer to Pressure Ports - Air Check and Parts Description for pressure apply points and for component/location description.
Possible causes of no 3rd gear are listed in the flowchart on the succeeding page.
Verify TRANSMISSION ISS and TRANSMISSION OSS read correctly on Scan tool.
Make sure the pressure control, shift 2, shift 3 and shift 4 solenoids are not intermittently sticking. A sticking shift solenoid 4 may cause 4th gear to be applied from an initial start resulting in no 3rd gear. Audible sound should be similar for all solenoids. A muffled tone indicates the need for replacement.
Check this pinout HERE
P0734 refer at ratio 4 gear, and the rocedure is the same.
Hope helps.

P0700 is a informative transmission code, about some problem there; the P0733 and P0734 is the specific problem there.
I would first try changing the fluid and filter. Although the fluid may look like it is brand new, with 100K on the fluid, I can assure you that even if those miles were all highway at steady speed and no load that the fluid has deteriorated and no longer lubricating the internal parts properly and that there is some debris in the ******.If codes return and shifting problems are still present, there is definite internal failure, possibly the pump or in the clutches.
DTC P0733The powertrain control module (PCM) uses the crankshaft position (CKP) sensor, input speed sensor (ISS) and output speed sensor (OSS) to determine engine speed, input shaft speed and output shaft speed. These sensor readings are used to determine the current gear ratio and RPM slip across the torque converter. The PCM uses this information from the sensors to determine if the commanded gear matches the actual gear. During normal driving conditions, the PCM will adapt main line pressure via the pressure control (PC) solenoid to prevent slipping and harsh shifts. Shift solenoid 3 is used to apply or release third gear clutch. The PCM controls 3rd gear by controlling the ground for shift solenoid 3. The PCM will turn the solenoid OFF, open the driver circuit, when 3rd gear is commanded On to apply 3rd clutch. Shift solenoid 3 is supplied ignition voltage from the fuel pump relay whenever the PCM commands the fuel pump relay ON. DTC P0733 sets when 3rd clutch still slips after the PCM has commanded high main line pressure.DTC Parameters
DTC P0733 will set if the PCM detects an incorrect actual 3rd gear ratio when 3rd gear is commanded On when:- The condition exists for longer than 3 seconds (2001)*- The condition exists for longer than 3 seconds, 1 minute is allowed to elapse, then condition exists again for longer than 3 seconds (2000)- The high main line pressure has been commanded- The transaxle is in a forward gear- The input speed is greater than 224 RPM- The vehicle speed is greater than 5 km/h (3 mph)- The speed noise parameter = NO- The steady state ratio fail counter equals 255 for an in-gear failure, or the shift fail counter is greater than 100 on a downshift or upshift to 3rd gear (128=0 or normal operation)DTC P0733 diagnostic runs continuously once the above conditions have been met.
DTC P0733 is a type A DTC for 2000, type B for 2001.**Applicable to vehicles built after June 2000.
Diagnostic AidsImportant: If DTCs P0745, P0746, P0756, P0758, P0761, P0763, P0766, P0768 or P0789 is set, diagnose that DTC first. A diagnosed PC solenoid, shift solenoid 2, 3 or 4 low/high circuit fault DTC may have caused DTC P0733 to set.Important: If a shift solenoid performance DTC P0783, 4th gear stuck ON, is set, diagnose that DTC first. A 4th gear stuck ON may cause no 3rd gear, no 2nd gear, or TCC stuck Off.
Refer to Pressure Ports - Air Check and Parts Description for pressure apply points and for component/location description.
Possible causes of no 3rd gear are listed in the flowchart on the succeeding page.
Verify TRANSMISSION ISS and TRANSMISSION OSS read correctly on Scan tool.
Make sure the pressure control, shift 2, shift 3 and shift 4 solenoids are not intermittently sticking. A sticking shift solenoid 4 may cause 4th gear to be applied from an initial start resulting in no 3rd gear. Audible sound should be similar for all solenoids. A muffled tone indicates the need for replacement.
Check this pinout HERE
P0734 refer at ratio 4 gear, and the rocedure is the same.
Hope helps.

Symptom:

P-0753 TRANS 3-4 SHIFT SOLENOID/TRANS RELAY CIRCUITS

When Monitored and Set Condition:

P-0753 TRANS 3-4 SHIFT SOLENOID/TRANS RELAY CIRCUITS

When Monitored: Continuously with the key on.

Set Condition: This code is set if the voltage detected on the 3-4 Shift Solenoid Control

Circuit at the PCM is different than the expected voltage.

POSSIBLE CAUSES

FUSED B(+) FEED TO THE TRANS CONTROL RELAY OPEN

3-4 SOLENOID WIRING HARNESS INTERMITTENT DEF

3-4 SOLENOID WIRING HARNESS OBSERVABLY DEF

SHIFT SOLENOID CONTROL CIRCUIT OPEN

SHIFT SOLENOID CONTROL CIRCUIT SHORT TO GROUND

SOLENOID AND HARNESS DEF (SOLENOID CONTROL CKT)

TRANSMISSION RELAY OUTPUT CIRCUIT OPEN

TRANSMISSION RELAY OUTPUT CIRCUIT SHORTED TO GND

PCM DEF (3-4 SOLENOID/TRANSMISSION)

PCM DEF (TRANS 3-4 SOL/TRANS RLY CKT)

POWERTRAIN CONTROL MODULE DEFECTIVE

POWERTRAIN CONTROL MODULE DEFECTIVE

POWERTRAIN CONTROL MODULE DEFECTIVE

SOLENOID AND HARNESS DEF (SOLENOID PACK CONN)

TEST COMPLETE
TRANSMISSION CONTROL RELAY DEFECTIVE

P0741 TCC STUCK OFF If the PCM detects high converter slip when the TCC is commanded on, then a DTC P0741 will set. The following conditions must exist for two times during the same ignition cycle. This code will set for all the same reasons that a P1870 will set: • The TCC duty cycle is greater than 50% • The TCC slip speed is greater than 180 RPM for 7 seconds • TCC slip in 3rd gear on 4L80-E transmissions Known causes for P0741: • Worn TCC valve bores in the valve body • Damaged or worn pump bearing seal • Defective TCC PWM or TCC apply solenoids • Restricted separator plate solenoid feed orifice • Defective converter • Computer reprogram • Channel plate sleeve & turbine shaft sealing ring damage I would suggest changing fluid and filter & reset pcm.

you will need the instrument cluster replaced. there are several companies that rebuild them, take it to a qualified repair shop, I'm sure they have a place they deal with to repair these. you will need to send yours in, as they usually want the old one first, to program mileage.